1. Field of the Invention
The present invention relates to surgical scissors which have argon plasma coagulation capability.
2. Brief Description of the Related Art
Controlling or arresting blood loss is of high priority during surgery so as to avoid or minimize the necessity of introducing foreign blood or blood products into a patient. This has increased in importance due to concern over contamination of the blood supply by viral agents which cause, for example, acquired immune deficiency syndrome (AIDS), hepatitis, and the like.
Standard means for controlling traumatic and surgical blood loss are electrosurgical generators and lasers, which respectively direct high-frequency electrical currents or light energy to localize heat in bleeding vessels so as to coagulate the overlying blood and vessel walls.
Argon beam coagulators additionally have been demonstrated to be effective tissue coagulators. Examples of argon beam coagulators for use in open surgery can be found in U.S. Pat. No. 4,040,426 to Morrison and U.S. Pat. No. 4,781,175 to McGreevy. Argon beam coagulators for use rigid and flexible endoscopy also are known. An example of a device for flexible endoscopy may be seen in U.S. Pat. No. 5,207,675 to the present inventor. In some embodiments in that patent, the inventor disclosed dual modality devices that could be used either for argon plasma coagulation or for traditionally electrocautery in an endoscopic environment. The inventor also disclosed an embodiment having the dual modality of argon plasma coagulation and endoscopic biopsy forceps. In that embodiment, argon plasma coagulation could be used by a surgeon while the biopsy forceps were withdrawn inside the flexible endoscopic tube. The biopsy forceps could then be extended and used, but argon plasma coagulation was not performed with the biopsy forceps extended from the end of the tube.
Surgical scissors have been known for many years. More recently, surgical scissors have been provided with electrosurgical capability such that the blades of the scissors may be used both to cut and to cauterize tissue. Electrosurgical scissors having both poles of electrosurgical energy exposed on the surface of the surgical blades have been referred to as “bipolar” electrosurgical scissors.
An example of bipolar electrosurgical scissors for use in open surgery can be found in U.S. Pat. No. 5,658,281, which is hereby incorporated by reference. An open surgery embodiment of U.S. Pat. No. 5,658,281 is shown in FIG. 1. Bipolar scissors 10 has first and second shearing members 11 and 12, as shown in FIG. 1. The shearing members 11 and 12 are connected by a pivoting joint 13 to allow scissors-like motion of the shearing members 11 and 12. Each shearing member 11 and 12 has a distal end 14 and a shearing surface 15 located between the pivoting joint 13 and the distal end 14. The distal ends 14 of the shearing members 11 and 12 are the ends designed to contact tissue. Each shearing surface 15 is bounded on one side by a cutting edge 16. Each shearing member 11 and 12 also has an exterior surface 17. The exterior surfaces 17 are the portions of each shearing member 11 and 12 which are exposed when the shearing members 11 and 12 are in a closed, or mated position. The exterior surfaces 17 are generally opposite the shearing surfaces 15 on each shearing member 11 and 12.
Electrical connections 19 are located on the scissors 10 for receiving two poles 20 and 21 of bipolar electrosurgical energy. The electrosurgical energy is high-frequency electrical energy, and thus the two poles 20 and 21 are referenced as a first pole 20 and a second pole 21, respectively. The electrical connections 19 receive the two poles 20 and 21 from an electrosurgical generator. The two poles 20 and 21 are then conducted to different regions on the surgical scissors 10. The arrangement of the different conductive regions 22 makes the bipolar scissors 10 more useful to surgeons than previous designs. In particular, the conductive regions 22 are positioned on the shearing members 11 and 12 such that both poles 20 and 21 are exposed to tissue on each shearing member 11 and 12, even when the scissors 10 are in a closed position. In an alternative embodiment of FIG. 1, the shearing surfaces 15 are each conductive, as shown in FIG. 2. The two shearing surfaces 15 meet during use, and therefore both shearing surfaces 15 are electrically connected to the same pole 20 to avoid an electrical short circuit. In this embodiment, the pivoting joint 13 does not need to be electrically insulated.
A second example of bipolar surgical scissors can be found in U.S. Pat. No. 6,283,963, which is hereby incorporated by reference. In a first embodiment of the bipolar electrosurgical scissors in that patent, the electrical insulation extends into the first and second cutting blades such that ⅓ of their distal tip is uninsulated. In a second embodiment of the bipolar electrosurgical scissors of that patent, the electrical insulation extends into the first and second cutting members such that they are entirely insulated except for their corresponding cutting edges.
Laparoscopic embodiments of bipolar surgical scissors also are known. Examples of such embodiments can be seen in U.S. Pat. Nos. 5,658,281 and 6,464,701. A laparoscopic embodiment of bipolar surgical scissors from U.S. Pat. No. 5,658,281 is shown in FIG. 2.
The present invention provides dual or trimode capabilities for surgical scissors such that the dual mode surgical instrument can be used simply to cut tissue, simply to coagulate tissue via argon plasma coagulation, or can be used to simultaneously cut tissue and to coagulate tissue via argon plasma coagulation. A trimodal embodiment provides the user with the flexibility to cut tissue and coagulate tissue either via argon plasma coagulation or via traditional electrocautery.